bigbatch.py

with open("bigbatch.csv", "w") as f:
    f.write("""x,y
1,2
3,4
""")

guild.yml

bigbatch: {}

train-batch:
  exec: guild run train @bigbatch.csv x="${x}" -y
  flags:
    x:
      required: yes
  requires:
    - operation: bigbatch
      select: bigbatch.csv
  sourcecode:
    dest: .

train:
  flags-import: all

train.py

x = 0
y = 0

print("x=%s" % x)
print("y=%s" % y)